Analyzing the spatial difference and convergence of ecological common prosperity (ECP) in the Yellow River Basin (YRB) will be beneficial for the environmental governance and multi-regional economic coordination. Based on the panel data of 97 cities in the YRB from 2003 to 2019, this paper measured and analyzed the index of ECP, the Gini coefficient of ECP, and the convergence of ECP. The results indicate that the ECP of YRB shows a steady growth trend (with an average growth rate of 4.71% yearly) and the overall differences are low (average Gini coefficient is 0.1509 from 2003 to 2019). In different areas, the Gini coefficient between the medium-stream and downstream of YRB is the largest (average value of Gini coefficient is 0.1561). From the decomposition of the overall differences of ECP, the contribution degree of the density of transvariation is the highest for annual average, with a contribution rate of 43.37%, the rate of intra-regional and the inter-regional differences are 31.86% and 24.77%, respectively. The results indicate that the overall differences of ECP in YRB are getting smaller because of cooperation and governance, but the differences between and within regions exist because of geographical feature. There is a significant spatial β convergence trend of ECP, the convergence rate in the upstream and downstream area is faster under the economic geographical matrix than others, and the rate in the medium-stream area is faster under the administrative adjacency matrix. Therefore, strengthening economic and environmental cooperation between and within regions is more beneficial to achieve a better quality of life, as well as the long-term goals of 2035.

The Chinese government is implementing a Synergizing the Reduction of Pollution and Carbon Emissions (SRPC) strategy to shift to green development. This study aims to assess whether a good intellectual property (IPR) environment is conducive to SRPC in Chinese cities. Based on data from 284 cities in China from 2004–2019, we employ the Driver-Pressure-State-Impact-Response-Management (DPSIRM) model to measure SRPC levels at the city level. We then use China's Intellectual Property Model City (IPMC) pilot policy as a quasi-natural experiment and apply a multi-period difference model to investigate the impact of establishment on urban SRPC. The study finds that the IPMC pilot policy promotes urban SRPC, and the findings hold after rigorous robustness tests. The mechanism is that the IPMC pilot policy promotes green technology innovation (GTI), draws government attention, and optimizes elements allocation. In addition, the heterogeneity test shows that the effect is greater in the Northeast cities as well as in small and medium-sized cities, while the effect is not significant in the West. Our findings provide theoretical and practical insights into how China can enhance IPR protection to advance SRPC.